package lab05;

/**
 * Created by 其 on 2016/5/6.
 */
import java.net.*;
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.security.spec.*;
import javax.crypto.interfaces.*;
import java.security.interfaces.*;
import java.math.*;

public class ComputeTCPClient {
    public static void main(String srgs[]) throws Exception{
        try {
            KeyGenerator kg=KeyGenerator.getInstance("DESede");
            kg.init(168);
            SecretKey k=kg.generateKey( );
            byte[] ptext2=k.getEncoded();
            //String kstr=parseByte2HexStr(kb);
            //创建连接特定服务器的指定端口的Socket对象
            Socket socket = new Socket("192.168.43.2", 4421);
            //获得从服务器端来的网络输入流
            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            //获得从客户端向服务器端输出数据的网络输出流
            PrintWriter out=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
            //创建键盘输入流，以便客户端从键盘上输入信息
            BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
            FileInputStream f3=new FileInputStream("Skey_RSA_pub.dat");
            ObjectInputStream b2=new ObjectInputStream(f3);
            RSAPublicKey  pbk=(RSAPublicKey)b2.readObject( );
            BigInteger e=pbk.getPublicExponent();
            BigInteger n=pbk.getModulus();
            //System.out.println("e= "+e);
            //System.out.println("n= "+n);
            //byte ptext2[]=kstr.getBytes("UTF8");
            BigInteger m=new BigInteger(ptext2);
            BigInteger c=m.modPow(e,n);
            //System.out.println("c= "+c);
            String cs=c.toString( );
            out.println(cs);  //通过网络传送到服务器
            System.out.print("请输入待发送的数据：");
            String s=stdin.readLine(); //从键盘读入待发送的数据
            Cipher cp=Cipher.getInstance("DESede");
            cp.init(Cipher.ENCRYPT_MODE, k);
            byte ptext[]=s.getBytes("UTF8");
            byte ctext[]=cp.doFinal(ptext);
            String str=parseByte2HexStr(ctext);
            out.println(str);  //通过网络传送到服务器
            String x=s;
            MessageDigest m2=MessageDigest.getInstance("MD5");
            m2.update(x.getBytes( ));
            byte a[ ]=m2.digest( );
            String result="";
            for (int i=0; i<a.length; i++){
                result+=Integer.toHexString((0x000000ff & a[i]) |
                        0xffffff00).substring(6);
            }
            System.out.println(result);
            out.println(result);
            str=in.readLine();//从网络输入流读取结果
            System.out.println( "从服务器接收到的结果为："+str); //输出服务器返回的结果
        }
        catch (Exception e) {
            System.out.println(e);
        }
        finally{
            //stdin.close();
            //in.close();
            //out.close();
            //socket.close();
        }
    }
    public static String parseByte2HexStr(byte buf[]) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < buf.length; i++) {
            String hex = Integer.toHexString(buf[i] & 0xFF);
            if (hex.length() == 1) {
                hex = '0' + hex;
            }
            sb.append(hex.toUpperCase());
        }
        return sb.toString();
    }

    public static byte[] parseHexStr2Byte(String hexStr) {
        if (hexStr.length() < 1)
            return null;
        byte[] result = new byte[hexStr.length()/2];
        for (int i = 0;i< hexStr.length()/2; i++) {
            int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);
            int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);
            result[i] = (byte) (high * 16 + low);
        }
        return result;
    }
}

